diff --git a/tests/io/test_convert.py b/tests/io/test_convert.py
index aa7ba78a..cf97f700 100644
--- a/tests/io/test_convert.py
+++ b/tests/io/test_convert.py
@@ -1,14 +1,22 @@
+import os
+import shutil
+import unittest
+
 import numpy as np
 
 from wfdb.io.record import rdrecord
 from wfdb.io.convert.edf import read_edf
+from wfdb.io.convert.csv import csv_to_wfdb
+
 
+class TestEdfToWfdb:
+    """
+    Tests for the io.convert.edf module.
+    """
 
-class TestConvert:
     def test_edf_uniform(self):
         """
         EDF format conversion to MIT for uniform sample rates.
-
         """
         # Uniform sample rates
         record_MIT = rdrecord("sample-data/n16").__dict__
@@ -60,7 +68,6 @@ def test_edf_uniform(self):
     def test_edf_non_uniform(self):
         """
         EDF format conversion to MIT for non-uniform sample rates.
-
         """
         # Non-uniform sample rates
         record_MIT = rdrecord("sample-data/wave_4").__dict__
@@ -108,3 +115,65 @@ def test_edf_non_uniform(self):
 
         target_results = len(fields) * [True]
         assert np.array_equal(test_results, target_results)
+
+
+class TestCsvToWfdb(unittest.TestCase):
+    """
+    Tests for the io.convert.csv module.
+    """
+
+    def setUp(self):
+        """
+        Create a temporary directory containing data for testing.
+
+        Load 100.dat file for comparison to 100.csv file.
+        """
+        self.test_dir = "test_output"
+        os.makedirs(self.test_dir, exist_ok=True)
+
+        self.record_100_csv = "sample-data/100.csv"
+        self.record_100_dat = rdrecord("sample-data/100", physical=True)
+
+    def tearDown(self):
+        """
+        Remove the temporary directory after the test.
+        """
+        if os.path.exists(self.test_dir):
+            shutil.rmtree(self.test_dir)
+
+    def test_write_dir(self):
+        """
+        Call the function with the write_dir argument.
+        """
+        csv_to_wfdb(
+            file_name=self.record_100_csv,
+            fs=360,
+            units="mV",
+            write_dir=self.test_dir,
+        )
+
+        # Check if the output files are created in the specified directory
+        base_name = os.path.splitext(os.path.basename(self.record_100_csv))[0]
+        expected_dat_file = os.path.join(self.test_dir, f"{base_name}.dat")
+        expected_hea_file = os.path.join(self.test_dir, f"{base_name}.hea")
+
+        self.assertTrue(os.path.exists(expected_dat_file))
+        self.assertTrue(os.path.exists(expected_hea_file))
+
+        # Check that newly written file matches the 100.dat file
+        record_write = rdrecord(os.path.join(self.test_dir, base_name))
+
+        self.assertEqual(record_write.fs, 360)
+        self.assertEqual(record_write.fs, self.record_100_dat.fs)
+        self.assertEqual(record_write.units, ["mV", "mV"])
+        self.assertEqual(record_write.units, self.record_100_dat.units)
+        self.assertEqual(record_write.sig_name, ["MLII", "V5"])
+        self.assertEqual(record_write.sig_name, self.record_100_dat.sig_name)
+        self.assertEqual(record_write.p_signal.size, 1300000)
+        self.assertEqual(
+            record_write.p_signal.size, self.record_100_dat.p_signal.size
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()